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(CNN)"Irving 911. What is your emergency?"

"Help, help! My dad shot me, my sister, I'm dying, I'm dying!"

On New Year's Day 2008, Yaser Abdel Said took his two daughters, 18-year-old Amina and 17-year-old Sarah, for a ride in his taxi. Hours later, the girls' lifeless bodies were found, with multiple gunshots wounds, in Yaser's abandoned cab.

Yaser Abdel Said, 58

Wanted in the slayings of his daughters, Amina Said and Sarah Said

On the run since January 2008

Has ties to New York, Texas, Virginia, Canada and Egypt

Before she died, Sarah Said made a brief, desperate call for help.

By the time the police located the cab, the sisters were dead, and Yaser Said had disappeared, along with his handgun and all of his savings. He hasn't been seen since.

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'I failed my kids'

Patricia Owens was just 15 in 1987 when she met 30-year-old Egyptian immigrant Yaser Said at the convenience store where he worked. They had only known each other a few weeks when he declared he wanted to marry her, convincing her parents that he could provide her with a comfortable life.

At 16, she gave birth to their son, Islam. Then came Amina in 1989 and Sarah in 1990. By age 18, Patricia was a mother of three.

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Despite the assurances Yaser gave the Owens family, he was not able to provide for his wife and children. According to Patricia, she worked full time to support the family while her husband hardly worked, driving a taxi every now and then.

Worse, Patricia alleges that Yaser was abusive.

"It was three or four times a week that he would hit me or kick me. ... I wasn't allowed to talk to my family on the phone unless he was there, and it was on the speakerphone. And as time went by, he would threaten me, like if I said anything to anybody that he would hurt them.

"Yaser always had a gun on him, and he would always go to the gun range to practice shooting. He had threatened before to kill my mom, and to kill my dad."

In 1998, Amina and Sarah, then ages 9 and 8, told their grandmother that Yaser had abused them, too. An investigation followed and in December 1998, Yaser was indicted for sexual penetration of his daughters.

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Before the case could come to trial, Amina and Sarah recanted, claiming they made it all up. Absent their testimony, the case was dropped. Patricia believes her husband got to the girls and persuaded them to change their story.

Patricia's mother, sister and aunt remained convinced that Yaser had abused his daughters. Over their objections, Patricia, Amina and Sarah returned to Yaser -- a decision that haunts Patricia to this day.

"I can't give you a good reason why I went back, because there is no good reason. When I took them back, I failed my kids."

Escape to Oklahoma

Yaser remained a domineering figure with strict rules for his daughters as they entered their teen years. To ensure their obedience, he would follow Sarah and Amina in secret, videotaping their activities.

"He always carried his camera everywhere," according to Patricia. "Yaser was videoing them to see who they was talking to and make sure they get on the bus. When they was at school, he would be taping them to see what they were doing. ... He put a recorder in Amina's car. He would check her mileage. That was just the way that he controlled us."

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Sarah and Amina were forbidden to have boyfriends. That didn't stop them from trying to date in secret. When Yaser found out on Christmas Eve 2007, he was furious.

That night, Patricia was at work when Amina and Sarah ran in, crying and screaming. Yaser had been waving a gun around at them, threatening to kill them -- a threat they believed he was capable of carrying out.

Fearing for their safety, Patricia, her daughters and their boyfriends decided to leave town. That night, they drove to Tulsa, Oklahoma, where one of the boyfriends had a relative.

The five of them planned to start a new life in Tulsa, far from Yaser. Over the course of a few days, they rented an apartment and acquired furnishings. Patricia and one of the boys found jobs in the area.

It seemed like things were going to work out. Patricia was relieved. "After we got out of Texas, and we got to Oklahoma, it was just like a big old weight lifted off of my shoulders."

So why did she, Sarah and Amina make that fateful, final trip back to Texas?

A tragic return

Connie Moggio, Patricia's sister, thinks the girls were misled by their mother and would never have agreed to a reunion with their father. "Amina called me, she said, 'I'm never going back there, I'd rather die first than to ever go back there.' "

Patricia disputes this account. "If you knew my girls, you could have not forced them to do anything they did not want to do."

She contends that all three agreed to return -- to attend a New Year's Eve party, visit her mother's grave and finish out the school year before returning to Tulsa for good.

Whatever their reasons, Patricia, Amina and Sarah returned to Texas.

"I admit I made a mistake. I came back here. But I thought I was doing the right thing for Amina, for her schooling. I didn't know I was coming back for my daughters to be murdered."

A few days after their return, Patricia and her daughters met with Yaser. He asked Amina and Sarah to get into his taxi so the three of them could get something to eat, telling Patricia they would return soon but none of them ever did.

Where is Yaser?

Yaser drove his cab to a secluded spot where, authorities believe, he shot both his daughters multiple times.

From Sarah's 911 call, police tried to triangulate their location from cell tower data but were unable to locate them in time.

Yaser Said has been on the run since that day, January 1, 2008. He has birthmarks on both sides of his neck and a scar on his left eyebrow. He frequently wears dark sunglasses, even indoors. He's also a frequent customer of Denny's and IHOP. He smokes Marlboro Light cigarettes and enjoys smoking a hookah.

If you've seen Yaser Said or know anything about his whereabouts, remember, he may be armed and dangerous. So please call 1-866-THE-HUNT or go to our website at CNN.com/TheHunt. You can remain anonymous; we'll pass your tip on to the proper authorities. And if requested, will not reveal your name.